package com.imooc.redis;

import com.alibaba.fastjson.JSON;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.ScanParams;
import redis.clients.jedis.ScanResult;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by ${User} on 2018/10/19
 */
@Service
public class RedisService {
    @Autowired
    private JedisPool jedisPool;

    /**
     * 获取当前对象
     * @param <T>
     * @param prefix
     * @param key
     * @param clazz
     * @return
     */
    public <T> T get(KeyPrefix prefix, String key, Class<Integer> clazz){
        Jedis jedis =null;
        try {
            jedis = jedisPool.getResource();
            //生成真正key
            String realKey = prefix.getPrefix() + key;
            String str = jedis.get(realKey);
            T t = stringToBean(str, clazz);
            return t;
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 设置对象
     * @param prefix
     * @param key
     * @param value
     * @param <T>
     * @return
     */
    public <T> boolean set(KeyPrefix prefix,String key,T value){
        Jedis jedis =null;
        try{
             jedis = jedisPool.getResource();
            String str = beanToString(value);
            if (str == null || str.length() <= 0){
                return false;
            }
            //生成真正的key
            String realKey = prefix.getPrefix() + value;
            int seconds = prefix.expireSeconds();
            if (seconds <= 0){
                jedis.set(realKey,key);
            }else {
                jedis.setex(realKey,seconds,str);
            }
            return  true;
        }finally {
            returnToPool(jedis);
        }

    }

    /**
     * 判断key是否存在
     * @param prefix
     * @param key
     * @param <T>
     * @return
     */
    public <T> boolean exists(KeyPrefix prefix,String key){
        Jedis jedis =null;
        try{
            jedis = jedisPool.getResource();
            //生成真正的key
            String realKey = prefix.getPrefix()+ key;
            return  jedis.exists(realKey);
        }finally {
            returnToPool(jedis);
        }
    }
    //删除
    public boolean delete(KeyPrefix prefix,String key){
        Jedis jedis =null;
        try{
            jedis = jedisPool.getResource();
            //生成真正的key
            String realKey = prefix.getPrefix()+ key;
            Long del = jedis.del(realKey);
            return del>0;
        }finally {
            returnToPool(jedis);
        }
    }
    //增加
    public <T> Long incr(KeyPrefix prefix,String key){
        Jedis jedis =null;
        try{
            jedis = jedisPool.getResource();
            //生成真正的key
            String realKey = prefix.getPrefix()+ key;
            return jedis.incr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 减少值
     * @param prefix
     * @param key
     * @param <T>
     * @return
     */
    public <T> Long decr(KeyPrefix prefix,String key){
        Jedis jedis =null;
        try{
            jedis = jedisPool.getResource();
            //生成真正的key
            String realKey = prefix.getPrefix()+ key;
            return jedis.decr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    public boolean delete(KeyPrefix prefix){
        if(prefix == null){
            return false;
        }
        List<String> keys = scanKeys(prefix.getPrefix());
        if(keys ==null ||keys.size() <=0){
            return  true;
        }
        Jedis jedis =null;
        try{
            jedis=jedisPool.getResource();
            jedis.del(keys.toArray(new String[0]));
            return  true;
        }catch (final Exception e){
            e.printStackTrace();
            return false;
        }finally {
            if (jedis ==null){
                jedis.close();
            }
        }

    }
    public List<String> scanKeys(String key){
        Jedis jedis =null;
        try{
            jedis = jedisPool.getResource();
            List<String> keys = new ArrayList<>();
            String cursor ="0";
            ScanParams sp = new ScanParams();
            sp.match("*"+key+"*");
            sp.count(100);
            do{
                ScanResult<String> ret = jedis.scan(cursor, sp);
                List<String> result = ret.getResult();
                if(result!=null && result.size()>0){
                    keys.addAll(result);
                }
                cursor = ret.getStringCursor();
            }while (!cursor.equals("0"));
            return keys;
        }finally {
            if (jedis !=null){
                jedis.close();
            }
        }
    }

    public static <T> String beanToString(T value){
        if(value == null){
            return null;
        }
        Class<?> clazz = value.getClass();
        if(clazz == int.class || clazz== Integer.class){
            return ""+value;
        }else if (clazz == String.class){
            return (String)value;
        } else if (clazz == long.class || clazz == Long.class) {
            return  ""+value;
        }else {
            return JSON.toJSONString(value);
        }
    }

    @SuppressWarnings("unchecked")
    public static <T> T stringToBean(String str,Class<T> clazz){
        if(str ==null || str.length()<=0 ||clazz ==null){
            return null;
        }
        if(clazz == int.class || clazz ==Integer.class){
            return (T)Integer.valueOf(str);
        }else if (clazz ==String.class){
            return (T)str;
        }else if (clazz == long.class || clazz == Long.class){
            return (T) Long.valueOf(str);
        }else {
            return JSON.toJavaObject(JSON.parseObject(str),clazz);
        }


    }

    private void returnToPool(Jedis jedis){
        if(jedis !=null){
            jedis.close();
        }
    }
}
